[PATCH 3.12 083/142] bfa: Fix undefined bit shift on big-endian architectures with 32-bit DMA address

[Jiri Slaby]

From: Ben Hutchings <ben@xxxxxxxxxxxxxxx>

3.12-stable review patch.  If anyone has any objections, please let me know.

===============

commit 03a6c3ff3282ee9fa893089304d951e0be93a144 upstream.

bfa_swap_words() shifts its argument (assumed to be 64-bit) by 32 bits
each way.  In two places the argument type is dma_addr_t, which may be
32-bit, in which case the effect of the bit shift is undefined:

drivers/scsi/bfa/bfa_fcpim.c: In function 'bfa_ioim_send_ioreq':
drivers/scsi/bfa/bfa_fcpim.c:2497:4: warning: left shift count >= width of type [enabled by default]
    addr = bfa_sgaddr_le(sg_dma_address(sg));
    ^
drivers/scsi/bfa/bfa_fcpim.c:2497:4: warning: right shift count >= width of type [enabled by default]
drivers/scsi/bfa/bfa_fcpim.c:2509:4: warning: left shift count >= width of type [enabled by default]
    addr = bfa_sgaddr_le(sg_dma_address(sg));
    ^
drivers/scsi/bfa/bfa_fcpim.c:2509:4: warning: right shift count >= width of type [enabled by default]

Avoid this by adding casts to u64 in bfa_swap_words().

Compile-tested only.

Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Reviewed-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Acked-by: Anil Gurumurthy <anil.gurumurthy@xxxxxxxxxx>
Fixes: f16a17507b09 ('[SCSI] bfa: remove all OS wrappers')
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
 drivers/scsi/bfa/bfa_ioc.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/bfa/bfa_ioc.h b/drivers/scsi/bfa/bfa_ioc.h
index 90814fe85ac1..d5b3f66f0ebd 100644
--- a/drivers/scsi/bfa/bfa_ioc.h
+++ b/drivers/scsi/bfa/bfa_ioc.h
@@ -72,7 +72,7 @@ struct bfa_sge_s {
 } while (0)
 
 #define bfa_swap_words(_x)  (	\
-	((_x) << 32) | ((_x) >> 32))
+	((u64)(_x) << 32) | ((u64)(_x) >> 32))
 
 #ifdef __BIG_ENDIAN
 #define bfa_sge_to_be(_x)
-- 
2.1.0

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